Apparatus and method for heating paint



NOV. 16, 1954 Q 5 LEVEY 2,694,767

APPARATUS AND METHOD FOR HEATING PAINT Original Filed March 24, 1951 2 Sheets-Sheet 1 Guazave J. Levey INVENTOR.

NOV. 16, 1954 LEVEY 2,694,767

APPARATUS AND METHOD FOR HEATING PAINT Original Filed March 24, 1951 2 Sheets-Sheet 2 w Gustave J. Leve 3 ll 0% m ig X, INVENTOR. y

t I a 9 '4 J WW MW A 7' TOR/YE Y United States Patent Oflice Gustave S. Levey, Houston, Tex.

Continuation of application Serial No. 217,335,. March 24, 1951. This application March. 31, 1954,. Serial No.

Claims. (Cl. 219-38) The invention relates to aimethod and apparatus for uniformly and efficiently heating a fluid .in a receptacle, and more uniformly and efiiciently heating paint in, small quantities Without loss and more particularly in the originalmanufacturers container.

This application is a continuation of myprior application filed on March 24, 1951, bearing; Serial No. 217,335, now abandoned, for an invention in Apparatus and Method for Heating Paint. The present application is entitled to the benefit of the filing date of said earlier filed application for all common subject matter.

In preparing a paint for usein a spray gun to spray on a surface, it is necessary to have the paint of a viscosity so that it will readily flow through the spray nozzle in the spray gun. To this end, various type heaters have been proposed in the past in anendeavor to heat the paint in paint pots to make it of a proper viscosity so that it will flow readily through the spray gun on the one hand, while presenting a smooth finished painted iurface on the surface to which it is applied on-the other and.

Another method used to prepare the paint of the proper viscosity is to add various solvents to thin it whereby it will flow more easily. This is disadvantageous in that the solvents add an additional expense in the preparation of the paint, and the proper solvents must be; selected.

which evaporate at ditferent temperatures so that as such solvents progressively evaporate from the paint after while other portions or bodies of the paint will be overheated.

a hose to such heater whereby the paint may be conducted directly from the heater to the spray gun. This hose which connects the heater, pump and. spray gun may be as long as 35 to 50 feet and the amount of paint in the hose, heater and pump is of such quantity to make impractical such units for gallon or similar small nuantities of material, or if the spray operation calls for a diflerent color on each object being sprayed,

The present invention is, therefore, directed to v a method and apparatus for uniformlyheating a body of paint in small quantities and in the original receptacle. It being of great importance for ease of operation, speed, cleanliness, and practical acceptability that this receptacle be the original paint manufacturers metal container, for example the five gallon, gallon, quart or pint can. The apparatus is so designed that the heating operations may be efiiciently carried out and eliminates the necessity of cleaning either the heating element or any attendant conduits.

Another object of the present invention is tov rovide a method for heating paint in a receptacle by applying a concentrated supply of. heat energy to a predetermined area in such receptacle and utilizing such heat energy to create a circulation of the fluid along. a predetermined path. whereby portionsof the particularly to a method, and apparatus for within .the receptaclev In other type heaters, it has been proposed to connect- 2,694,767 Patented Nov. 16, 1954 body of fluid are continually moving upwardly and away from the area of localized heat while other portions of 1tlhe body of fluid are moving into the localized area of eat.

Still another object of the invention is to provide a method-for heating a body of paint which method uniformly heats the paint and eliminates cold spots' or hot spots in the paint being heated.

Another object of the invention is to provide an apparatus for uniformly and efificiently heating a body of paint which apparatus eliminates the necessity of cleaning the receptacle when changing colors of paint and which eliminates the cleaning of the heating element per se.

Stillanother object of the invention is to provide in an electrical heating attachment for heating a fluid, in a receptacle, a base, a heat conducting plate thereon to engage the bottom of the receptacle, a heating element to transmit heat to said plate, a ring to engage the top of the receptacle, and clamp means to rernovably secure said ring and base together as a unit and for compressing the receptacle between said ring and base and into intimate contact with said heat conducting plate.

Still another object of the invention is to provide an apparatus for heating paint in the container in which it is shipped, which apparatus comprises a base to receive the container, a ring to fit around the top of the container to facilitate pouring the paint from the container and to increase the volume of the original container whereby solvents may be added to the original container, and clamp means to compress such container between the ring and onto the base.

Still another object of the invention is to provide a ring to fit on a paint manufacturers original container which ring increases the volume of the original container whereby solvents may be added to the original container and. to facilitate pouring paint from the container and a handle secured to the ring to facilitate cleaning of the ring and aid in pouring.

Another object is to providev a paint heaterdevice including a ring to fit on the top of a container which ring is the only element in the heater which must be cleaned when reusing the device.

Another object of the invention is to provide a paint heating device wherein there is very little residual heat remaining in the device after the paint has reached the proper temperature which eliminates any detrimental overheating of the paint above such temperature after the device has shut off.

Still another object of the invention is to provide a heat conducting plate of a particular configuration to heat paint in an original manufacturers paint can, which plate is designed to receive and heat all manufacturers cans regardless of the configuration of the bottom of the can.

Still another object of the invention is to provide. an apparatus for applying center heat to a body of fluid in a receptacle to create a continuous upward flow of heat through the receptacle thereby circulating the fluid in the receptacle continually upwardly away from the point of application of the center heat.

Still another object of the invention is to provide in an apparatus for uniformly heating paint in a receptacle, a heat conducting plate to engage the bottom of such receptacle, said heat conducting plate decreasing in cross-section dimensiontoward the center thereof whereby heat is transmitted to the receptacle from the center which is the smallest cross-section dimension faster than at any other dimension to heat the paint in the center portion thereof.

Other objects and advantages of the invention will become more readily apparent from a consideration ofv the following description and drawings wherein:

Fig. 1 is a perspective view illustrating the preferred embodiment of the invention positioned on a receptacle;

Fig. 2 is a side elevation of the embodiment illustrated in Fig. 1;

F Fig. 3 is a bottom plan view of the device shown in Fig. 4 is a. vertical sectional view showing a construction of; the heat conducting plate, the base, therefor, and.

the ring to fit on top of the receptacle with the arrows indicating the circulation of the fluid within such receptacle;

Fig. is a partial vertical sectional view illustrating the preferred embodiment of the clamping means for retgining the ring and base in position on the receptacle, an

Fig. 6 illustrates a modified form of the heat conducting plate.

In Fig. 4, the original container, or paint can is illustrated generally by the numeral 2 and is shown with a fluid such as paint therein. A base 3 is provided to support the component parts of the heating device and the receptacle 2 when it is positioned thereon. A ring 5 is adapted to engage in the top 6 of the receptacle, such ring being provided with a suitable spout 7 whereby the material may be poured from the receptacle after the heating operation is completed.

This ring also increases the efiective volume of the can whereby necessary solvents, or other ingredients may be added without pouring any paint from the can 2.

The base 3 may assume any suitable configuration and is shown as being provided with a cup 8 which has the bottom 9 and sides 10 extending upwardly adjacent the side 11 of the hollowed-out portion 12 of the base 3. The cup and support may be secured together by any suitable means such as screws 14, with the cup being provided with suitable openings 15 and 16 to receive electrical conductors.

Secured to the base by any suitable means, such as screws 18, is a heat conducting plate 19 adapted to engage the bottom 20 of the receptacle 2.

Particular attention is directed to the configuration of this heat conducting plate in that it is provided with an annular portion 22 located substantially centrally of the heat conducting plate 19. It is to be noted that the cross-sectional dimension 23 of the portion 22 gradually diminishes on each side 24 toward the middle point 25 of the plate 19. It is to be further noted that the cross-sectional dimension of the portion 22 is somewhat thinner than the remaining cross-sectional dimension 26 of the plate 19. An ordinary heating element or hot plate under a gallon can would produce an ununiform heat increment in the paint causing overheating and solidification in spots due to lack of circulation.

The heating conducting plate 19, because of the gradual rise toward the center thereof as best seen in Fig. 4, fits all manufacturers cans. In other words, when the can 2, as shown in Fig. 4, is placed on the plate, the bottom 20 yields more readily adjacent the center thereof whereby such can tends to conform to the plate.

A heating element 27 of any suitable configuration is connected to a source of electrical energy by means of the conduit 28 extending through the opening 15. Such heating element heats the plate 19 which in turn heats the fluid in the receptacle 2. Due to the construction and configuration of the heat conducting plate 19, heat will be transferred from such plate to the receptacle faster through the portion 22 which is of a smaller cross-sectional dimension than the remainder of the heating plate. More particularly, heat will be transmitted upwardly through the center of the receptacle as denoted by the arrow 29 faster than at any other point on the heat conducting plate since the smallest dimension of the plate is at 25 and because the annular portion 22 on such plate directly contacts the bottom 20 of the can 2.

The heat conducted from the annular portion 22 of the plate and more particularly the concentrated heat energy supplied to the receptacle in the localized area adjacent the center of such receptacle is used to create a circulation of the fluid upwardly within the receptacle as denoted by the arrow 31. It is to be noted that this circulation is upwardly away from the area of localized heat and towards the top of the receptacle and thence radially outwardly as shown by the arrows 33 and then down along the side 4 of the can as illustrated by the arrows 34 and back toward the center adjacent the bottom of the receptacle as illustrated by the arrows 35. At this point, the fluid or paint moves into the area of localized heat and thence continues its movement upwardly again as previously described.

In this manner, the fluid within the receptacle is continuously circulating and the whole body of fluid is moving along the predetermined path as represented by the numerals 31, 33, 34, and 35. This circulation which is created the concentrated source of heat energy uniformly heats the paint in the receptacle and eliminates cold spots or over-heating of any particular portion of the receptacle since a portion of the fluid is continuously moving away from the point of concentrated energy while another portion of the body of fluid is continuously moving into the area of concentrated heat energy.

A thermostat 40 is provided to regulate the temperature of the heating conducting plate. This thermostat or thermostatic switch acts to break the circuit beween the conductor 28 and heating element 27 to stop the flow of electrical energy thereto. The thermostatic switch 40 can be set at any suitable temperature and if an inflammable material, such as paint, is being heated in the receptacle, then of course, it will be set at a point well below the flash point of such material. Generally speaking, the thermostat switch can be set at 25 to 50 above the normal operating temperature of the heat conductor plate since it is primarily provided to cut out the circuit when the receptacle is removed from engagement with the heat conducting plate 19.

In order to regulate the temperature of the fluid within the receptacle 2, a thermostatic switch 42 is provided to engage the side of the can. also connected into the electrical conductor 28 so as to stop the flow of electrical energy to the heat conducting plate when the temperature of the fluid in the receptacle has reached the desired temperature.

To insure an intimate contact between the thermostat 42 and the receptacle 4 and to insure intimate relationship between the heat conducting plate 19 and bottom 20 of the receptacle, suitable clamp means 44 are provided. This clamp also serves to retain the ring and base together with the receptacle compressed therebetween and on the base in engagement with the heat conducting plate 19.

Any suitable form of clamping means may be used and as illustrated in Fig. 5, arms 46 may extend upwardly from adjacent the base 3 and are provided with the eccentric connection 47 which is pivotally mounted on the pin 53 in arm 46. The upstanding arm 48 is secured by any suitable means to the eccentric connection 47 as shown at 49. The eccentric 47 is provided with a lever 50 and the arms 48 are provided with opening 51 to engage in suitable lugs 52 provided on the ring 5.

In the clamping means illustrated, the opening 51 would be engaged with the lugs 52 on ring 5, whereupon clockwise movement of the lever 50 pivots the arm 48 downwardly and about pivot pin 53 rotatably mounted in the upstanding arm 47. The lever moves the eccentric 47 slightly past the center of pin 53 to retain the ring 5 and base 3 clamped together. This compresses the receptacle 2 between the ring 5 and base 3 and firmly engages the heat conducting plate 19 with the bottom 20 of such receptacle. Reverse movement of the lever 50 disengages the clamping means and ring 5 and base 3. Two arms 46 may be provided on the base. The thermostatic switch 42 is arranged in a housing 55 extending upwardly from the base support and preferably is positioned with respect to the arms 46 which are diametrically opposed on the base 3 and extend upwardly therefrom so that when the clamping means pins the receptacle between the ring 5 and base 3 it will also move such receptacle slightly rearwardly into firm contact with the thermostatic switch When using the clamping means illustrated in the drawings it has been found preferable that the thermostatic switch be positioned substantially centrally between such arms so that the movement of the lever 50 in a clockwise direction tends to push the receptacle rearwardlsy while compressing it between the base 3 and ring If desired, a suitable indicating light 57 can be connected in the conduit 28 which will indicate when the thermostatic switch has broken the circuit which in turn indicates that the material is to the desired temperature in the receptacle.

Any suitable off and on switch can be provided on the electrical conduit 28 as illustrated at 59. A handle 60 is provided on the ring to facilitate pouring of the fluid, such as paint, from the receptacle. The top of the original paint can as illustrated at 61 may be placed on the ring during the heating operation to prevent foreign material from getting in the paint.

An alternate modification of the heat conducting plate This thermostatic switch is flu is illustratd in Fig. 6. It is to be noted that the annular raised portion illustrated in Fig. 4 is eliminated from this form of the heat conducting plate and in lieu thereof the heat conducting plate is provided with a gradual taper toward the middle thereof whereby a portion 62 is provided which gradually diminishes in cross-section and has its smallest cross-section dimension or thickness at 63. This form of the heat conducting plate also concentrates the heat energy generally in the portion designated by the arrow 62, which is substantially in the center of such plate whereby heat energy may be concentrated through this particular portion to effect the center heating of a fluid in a receptacle as heretofore described.

While it is believed that the invention is apparent by reason of the foregoing description, to further amplify and describe such invention it will be assumed that an inflammable material such as paint of a type to be sprayed on automobiles is to be heated in the receptacle.

Thermostat or thermostatic switch 40 is set to break the circuit at a temperature below the flash point of the solvent used in the paint. Thermostat or thermostatic switch 42 is set at the temperature to which it is desired to heat the paint and will also break the circuit when the circulating fluid or paint in the receptacle reaches such temperature.

As energy is supplied to the heating element 27, such energy will be dissipated more easily through the section of the heat conducting plate 19 which is of a smaller width or cross-sectional dimension than the remainder of the plate. In this manner heat is conducted into the receptacle adjacent to the middle thereof. This creates the circulation heretofore described and indicated by the arrows shown in Fig. 4 which in turn effects uniform and efficient heating of the paint. Such method of heating alos eliminates cold spots or hot spots in the paint being heated.

When the paint reaches the desired temperature at which the thermostatic switch 42 is set, such switch will open the circuit whereupon no further electrical energy will be supplied to the heating element 27. Due to the construction of the invention, there will be very little override heat to be transmitted to the paint. For example, assume that it is desired to heat the paint to about 150. In such event, thermostatic switch 42 is set so that it will open the circuit to the element 27 when the paint reaches this temperature; however, it is readily appreciated that residual heat still remains in the heating element 27 after the supply of electrical energy thereto has been shut off. This energy is in turn transmitted to the heating conducting plate 19 and to the paint, but since the heat conducting plate is of relatively thin construction there will be very little, if any, residual heat left in this element when the device is turned off and the rise in temperature of the paint in the receptacle due to the residual heat in the heating element 27 and the heating conducting plate 19 will generally not amount to more than or This is highly desirable in that it is easier to regulate the final temperature of the paint. No guess work is involved in trying to estimate the override in temperature due to any residual heat in the heat conducting plate 19 and it is easier to set the thermostatic switch 42 knowing that the paint will not rise above this temperature to a point which might damage the paint material.

It is to be noted that the ring 5 is the only part of the device which needs cleaning before reuse.

Broadly the invention relates to a method and apparatus for heating a fluid in the original receptacle in which it is shipped and more particularly the invention relates to a method of applying a center heat to paint in a receptacle and for circulating the paint in the receptacle so that portions of such paint are continually moving away from the point of application of heat and are continually moving toward the point of application of such heat.

What is claimed is:

1. In an electrical heating attachment for heating a fluid in a receptacle, a base, a heat conducting plate thereon to engage the bottom of the receptacle, a heating element to transmit heat to said plate, said heat conducting plate having its smallest cross-sectional dimension adjacent the central portion thereof whereby heat transmitted to said plate from said element will be transferred faster from said plate adjacent such smaller dimension portion, a ring to engage the top of the receptacle, clamp means to removably secure said ring and base together as a unit and for compressing the receptacle between said ring and base and into intimate contact with said heat conducting plate, and a thermostat to control the temperature of said heat conducting plate.

2. In an electrical heating attachment for heating a fluid in a recpetacle, a base, a heat conducting plate thereon to engage the bottom of the receptacle, a heating element to transmit heat to said plate, said heat conducting plate having its smallest cross-sectional dimension adjacent the central portion thereof whereby heat transmitted to said plate from said element will be transferred faster from said plate adjacent such smaller dimension portion, a ring to engage the top of the receptacle, a clamp means to removably secure said ring and base together as a unit and for compressing the receptacle between said ring and base and into intimate contact with said heat conducting plate and a thermostat to control the temperature of the fluid in the receptacle.

3. In an electrical heating attachment for heating a fluid in a receptacle, a base, a heat conducting plate thereon to engage the bottom of the receptacle, a heating element to transmit heat to said plate, said heat conducting plate having its smallest cross-sectional dimension adjacent the central portion thereof whereby heat transmitted to said plate from said element will be transferred faster from said plate adjacent such smaller dimension portion, a ring to engage the top of the receptacle, a clamp means to removably secure said ring and base together as a unit and for compressing the receptacle between said ring and base and into intimate contact with said heat conducting plate, a thermostat to control the temperature of said heat conducting plate, and a thermostatli to control the temperature of the fluid in the receptac c.

4. In an electrical heating attachment for heating a fluid in a receptacle, a base, a heat conducting plate thereon to engage the bottom of the receptacle, a heating element to transmit heat to said plate, a ring to engage the top of the receptacle, and clamp means to removably secure said ring and base together as a unit and for compressing the receptacle between said ring and base and into intimate contact with said heat conducting plate, said heat conducting plate decreasing in cross-section dimension toward the center thereof whereby heat is transmitted to the receptacle from the smallest cross-section dimension faster than at any other dimension.

5. In an electrical heating attachment for heating a fluid in a receptacle, a base, a heat conducting plate thereon to engage the bottom of the receptacle, a heating element to transmit heat to said plate, a ring to engage the top of the receptacle, and clamp means to removably secure said ring and base together as a unit and for cornpressing the receptacle between said ring and base and into intimate contact with said heat conducting plate, said heat conducting plate having a portion thereon of smaller cross-section dimension than the remainder of said plate whereby heat is transmitted from such portion at a faster rate than from the remainder of said plate.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,145,988 Hadaway et al July 13, 1915 1,391,863 Spangler Sept. 27, 1921 1,678,885 Thomas July 31, 1928 2,259,544 Black Oct. 21, 1941 2,314,467 Tubbs Mar. 23, 1943 

